How Remove values from Session in Asp.Net

Question

I have Session["ID"]="1,2,3,4,5" .

How I remove a single value(2 or any) from Session?

Answer 1

If you wanna remove first value, you can use;

var s = "1,2,3,4,5";
var result = string.Join(",", s.Split(',').Skip(1).ToList());
Console.WriteLine(result); // 2,3,4,5

If you wanna remove last value,

var s = "1,2,3,4,5";
var lastValue = s.Split(',')[s.Split(',').Length - 1];
var result = string.Join(",", s.Split(',').TakeWhile(c => !string.Equals(c, lastValue)).ToList());
Console.WriteLine(result); // 1,2,3,4

Answer 2

Its ugly, but you could try the following:

var numberToRemove = 3
var result = Session["ID"]
    .Replace(numberToRemove.ToString(), string.Empty)
    .Replace(",,",",")
    .Trim(',');
Session["ID"] = result;

or

var result2 = Session["ID"]
    .Split(',')
    .Where(s => s != numberToRemove.ToString())
    .Aggregate((s1, s2) => s1 += "," + s2);

Answer 3

You can split the string using the delimiter remove the items and then join the remaining strings using the delimiter

        var sessionIds = Session["ID"].Split(',').ToList();
        sessionIds.Remove("1");
        sessionIds.Remove("5");
        Session["ID"] = string.Join(",", sessionIds);

Answer 4

You an use Regex for that:

Session["ID"] = Regex.Replace(Session["ID"], "[15],|,[15]$", string.Empty);

Maybe there are whitespaces after each colon:

Session["ID"] = Regex.Replace(Session["ID"], "\s*[15],|,\s*[15]$", string.Empty);

Answer 5

string GetID = txtID.text;
var sessionIds = Session["ID"].ToString().Split(',').ToList();
sessionIds.Remove(GetID);
Session["ID"] = string.Join(",", sessionIds);